Is Price really the number one reason we buy things?
Yep, sure is.
If my budget maximum is $6000, regardless of payment method, then I can't even consider the $8000 or $9000 tub.
Good point about long term cost when comparing tubs of similar price point - but if you really can't swing that additional $1K now, then what? And you never really know your cost of having a particular tub until you have had it for some time.