1) A billion dollar industry is nothing when compared to the overall US economy. Also, reptile sales are typically run in the gray market, transactions are cash and carry in many cases, and very few hobbiests declare and pay taxes if they make a profit in a particular year. FedGov won't see a downside - as in, loss of revenue - to generating more regulations on it.
2) I'm licensed as a firearm manufacturer, so I'm working in a $33 billion industry that generates just over $5 billion just in tax revenue for the federal and state governments per http://nssf.org/impact/. I spend several hours each week engaged in activities solely to cover my rear end and keep me out of federal prison, time that would be much better spent doing something productive like cleaning up after my BP's.