I paid them well. Very well as a matter of fact. They left smiling and I saw them punching each other in the shoulder over 'the score'.
I paid them what the job was worth in my estimation. For 30 minutes hard work, I gave each guy $40 and gave the guy driving the car $10 for gas.
I got my trailer loaded up for under $100 and they got paid $80/hr. Plus a small 'benefit' if you really want to get into the weeds. That's what the job was worth to me.
And I bet you're proud of yourself too. Did you offer them insurance and health benefits? Did you make sure they filled out the proper paperwork for contract labor? Did you even ensure they were authorized to work in the US? Would you have covered medical expenses if one of them were hurt on the job?
Being facetious aside, you're not actually seeing the issues here. You seem to have already made up your mind on the subject, so I doubt anything I say here would change your view. I'll type it out anyway (hopefully concisely enough since I have several thoughts) that you might actually take another POV into consideration.
To quickly address Americans not wanting to do the work; a large part of this is because government programs provide incentives to sit on the couch and collect subsidies than to get a job. Meaning why get a job when you can get the same amount or potentially more for doing nothing. Take away the subsidies where the choice is get a job or starve, and I bet people would be a lot more willing to do that work.
You may have paid those guys well enough, but that is not always the case. I'm not going to say it's every person that's hanging around at Home Depot or whatever looking for day work, but many are illegal immigrants. They're not authorized to work in the US and shitty companies take advantage of that by paying pennies on the dollar in cash to what they would have to pay a US worker. Not to mention the company skirting around having to pay employment taxes and such.
That leads to the next point. These illegal day laborers are not offered the same protections as a US worker. Technically they may be covered in some aspects. Reality is if something happens they're not provided any protections. Pretend an illegal migrant's hand gets crushed on the job. Company: "I don't know who this guy is. There's no documentation of a labor contract. He isn't supposed to be here. I'm not liable for his injuries" Or from another aspect. The migrant isn't supposed to be in the country in the first place and likely fears deportation. There's a good chance the person wouldn't say anything about the injury in the first place and leave it untreated.
More to the point above, but on the wages side; illegal immigrants are generally reluctant to report wage violations such as underpayment or no compensation for overtime. They also lose the ability to negotiate their wages and depending on the industry lose access to unions. This provides zero pressure to companies to improve the quality of pay or working conditions.
Leading from that point and going back to paying illegal migrants pennies on the dollar. This also has the effect of driving wages down in that field. It's more that just natural capitalism or labor supply & demand. It's artificially driving wages down by creating downward pressure across the particular labor market. It provides employers the opportunity to underbid competitors by circumventing wage standards. In instances where employers would need to introduce better wages or incentives to attract legal workers, hiring illegal migrant at sub-standard wages prevents that wage market from improving organically; i.e. as stated it keeps the wages artificially low.
I know I was talking a little in hypothetical scenarios, but none of this is outside the realm of possibilities and likely happens a lot more that you would like to think or admit. So they're all valid points and this is just the tip of the iceberg with issues caused by hiring illegal migrants. I'm also not going to place the blame solely on illegal migrants either. Companies hiring them share that blame as well. If companies wouldn't be hiring illegal migrants, they wouldn't be coming here for work. But if illegal migrants didn't accept sub-par wages and such, companies wouldn't hire them in the first place. Bit of a catch 22.
Personal opinion on that, I think any company or individual caught employing illegal migrants should be fined heavily.
Anyway I see this is a wall of text so I'm going to stop here.