Sorry about that, but if you do not bother to keep your bike chain and drive train clean, you are begging for trouble. If you spend some serious cash for your bike, then why would you not take the time to learn how to care for it?
Depending on the once a year modified cleaning your bike store will do for your $25 checkup is foolish. First of all, the bike store is not going to do much for $25. If you never clean your bike, ya'd better fork over some dough and get a full drive train cleaning where the bike parts are removed and cleaned in a solution. But even this is NOT enough.
It only takes a few rides for gunk to build up on your chain and in and out of your derailleurs. Your chain has to be cleaned and lubed frequently if you are riding once or twice a week. Some folks clean and lube chain after each ride.
Go out right now and look at your bike. Is the chain all black and covered with what looks like black dirt? Are your back small wheels that wrap your chain covered in grim? Are your brake pads clean? And the list goes on and on.
I ran a bike clinic yesterday and one fellow showed up with a bike covered in black grim. Plus he was also using his bike pump incorrectly therefore he had not put air in his tires since last October. The pressure in his tires was round 50 PSI and he did not even know it.
Why spend gobs of money on a bike and then ignore it??
It is not like I am some mechanical genius but I have taken the time to learn how to maintain my bike. I can change a tire, I can clean my bike and I can lube my bike. If I do not know something I ask someone who knows bikes to help me. How hard is that!
Take care of your bike!