OP's profile has "I work as a developer at Viacom in London." so UK price may be more relevant than USD:
If you need to pay for the vaccination privately, you can either visit your GP surgery or a travel clinic. The price for the complete course of three doses ranges from £120 to £170.
Same source NHS:
The vaccine is usually only recommended if the potential risk of exposure to rabies is thought to be high and there is limited access.
for a trip in May 2015.
"Holiday" sounds like short duration and "mountain biking" (with family) not particularly remote.
So Yes avoidable.
You would never forgive yourself if your child did contract rabies there and you had opted out of the vaccination but then I doubt parents who buy their children cars only to find them wrapped round a lamppost the next day ever forgive themselves either - but parents still buy their children cars.
Fit for Travel
Rabies: spread through the saliva of an infected animal, usually through a bite, scratch or lick on broken skin. Particularly dogs and related species, but also bats. Risk is higher for those going to remote areas (who may not be able to promptly access appropriate treatment in the event of a bite), long stays, those at higher risk of contact with animals and bats, and children. Even when pre-exposure vaccine has been received, urgent medical advice should be sought after any animal or bat bite.