What's up with all the underfed snakes

[snakesRkewl]

How many snakes have you raised OP?

30 to 40 from hatchlings to a year old.
Almost every one of them reached 400 grams at 6 months, the ones that didn't were obviously picky eaters.
I feed rats only except to hatchlings that start out on asf fuzzies.

Have you determined that these undersized snakes are unhealthy or are they just smaller than you would like them to be?

smaller than I'd like them to be
I'm speaking of animals on the market, not mine or any I bought.

If they're just too small, in your opinion, what do you base this opinion on?

On all the hobbyist that show off their snakes growth on here and many other sites as well, and with my limited knowledge of keeping them.

If there are health issues, what have you done about that?

I haven't had any health issues that needed a vet, but if I did I have a local Vet that isn't too far from me that deals with reptiles and has a fairly good rep for doing so.

This isn't only my opinion, just me asking, "what up with that?" on snakes weights that are on the market