It's fundamental logic that unless your company provides something close to 100% of the employment market (as in, you are a complete monopolist on all economic activity), you are better off paying your workers as little as possible.
Your workers are a tiny portion of your customer base. Let some other sap pay theirs well.
Now, if you have other reasons to pay your workers well (competitive demand for their labor, high turnover, need for growth, motivation tied directly to output, etc), then it is also logical to come up with a nice-sounding fairy tale justifying your largess.
(Or you might actually be motivated by some kind of chivalristic noblesse oblige largess, and are tricking yourself - or socially signaling to your peers - by coming up with a 'logical' motivation for it. I wouldn't immediately assume this of HF, but I am not exactly a Fordian scholar. All I know about him is that he owned a factory that built cars, was a bit of an anti-semite, and also had a lot of opinions about how his employees should live their lives.)