@klidec I don't think location data is reliable enough for this use case, but I'll let Cameron speak definitively on that - although perhaps if your garage is far enough away from the front door, the Bluetooth signal could be used to discriminate? These limitations aren't unique to any particular smart lock, unfortunately.
As an alternative (less-ideal, for sure) solution, I think Sense behavior is defined per-lock (confirmation?), so you could have the garage lock be proximity unlock - if it isn't a problem that it unlocks even when you don't come home via the garage - and the front door be notification based, but you'd have to take out your phone to trigger unlocking. This is another use case that would be cleaned up by Keypad (see here for the functionality it is planning to provide - http://community.lockitron.com/t/bolt-keypad-faq/2015/7) , since you could touch the unlock button there, feasibly, rather than having to dig for your phone.