My dog doesn't like toys?

I have a labradoodle puppy that I got from a shelter. He's really smart, really sweet, and kinda shy, but virtually nothing wrong with him physically. His owners just surrendered him cause they were moving. He's about 8 months and I've had him for about 4 weeks now, and for the life of me, he doesn't like toys? I've tried squeaky chew toys, scented chew toys, rope toys, and stuffed toys and he just seems uninterested in all of it. I also tried one of those puzzle toys to get the food and he just lost interest in that too.

I exercise him regularly and he eats good, but I'm just not sure why he has no interest in toys? The only thing that interests him are things he can actually eat. He absolutely loves bully sticks but I don't want to give them to him all the time? (Can I? I saw somewhere that it wasn't healthy). Bully sticks are also pretty expensive so I can't just keep giving them to him... Does anyone have any advice or alternatives?