You could always get him to have the vet castrate them, or get the vet to them yourself.
There are breeders who have handling facilities to keep home bred bulls to sell as stores, and fatteners who also have facilities to keep entire males to slaughter weight.
Intact males often grow quicker and there is a risk of things like bleeding, swelling or infections with any method of castration, even a slight risk of death, so if the risks of castration outweigh the benefits in your system, then farmers won't castrate.
However, the prices for entire bull beef is now dropping so maybe some are trying to get rid, I know of one farmer who has always sold his entire bulls as stores, and is on the verge of retirement but is going to castrate this year because otherwise he'll lose a lot.