Is it really acceptable to use the item being purchased as collateral on the very loan taken to buy that something?

Of course. That's what car loans & home loans do. If you don't pay, they repossess & sell the car or house. Whatever balance is due after the collateral is sold they sue you for.

Yup, that's what mortgages and car loans are.

I am living in the northeast u.s.a.; most of my professional time has been spent as a technology instructor. '

Either that or you are a bored 12 year old.

Yes it is.