As you may or may not know, if your Mac came with Lion you cannot install Snow Leopard, since that is one method Apple uses to force Lion on users. It's a practice I find offensive, yet it's no surprise since it's the Apple Way.
Offering flexibility to their customers is something they'd never consider. Apple is very good as a dictatorship. Their old CEO was certain he knew what was best, and built a following of yes men and women to back him.