The front suspension components tend to wear out on these cars. The strut bearings (top of the strut) wears out, and you replace those at the same time as the spring seat rubber cushions. Either of them failing can lead to a crunching noise.
Not only that, but the lower control arms have bushings in them that wear out with time/miles. When they wear out your alignment also goes out of whack and you'll eat tires up.
If you see cupping or uneven wear in the front, that's most likely it.
If you had the end links replaced and did NOT have it aligned, that could exacerbate the problem.
An alignment shop should check the ball joints, lower control arm bushings and related items to confirm that they CAN align the parts.
These are not bad cars, so you shouldn't have a lot of repair shops. It almost sounds like the shop you're going to is a little too eager to have you pay for things without proper diagnostics.
Check some of the volvo forums for a local independent shop near you - they live on reputation, unlike a dealer. Tires don't have to be what the dealer recommends, but General Grabber UHP are good ones, Michelin Primacy MXM4s are good too and Continental DWS are excellent tires too.
If you *need* tires now, you might want to put something cheap on it if they just wear out before you get the alignment and bushings/bearings issues solved.
Finish everything off with a FOUR WHEEL alignment to ensure all tires are rolling properly, and ensure the tire pressures are correct.
Your crunching noise could be compounded by all these things, and none of them are really crazy expensive or a big problem.
Good luck, and please let us know by commenting below what the actual problem is/was when you get it resolved.
I'm linking you a comprehensive suspension kit so you can see what's involved (parts and cost) and then you could find a reliable/trustworthy local mechanic to install it if you're not sure you want to do it yourself.
Volvo Comprehensive Suspension Kit XC90 XC90FRONTREARKIT