Though I'm of an opinion that each should bond with their bosses, what I've generally experienced is what is shared below-
Bonding over a period of time leads to cohesiveness; and cohesiveness leads to things happening on a very personal level. Trust me when I say then, bonding crosses the professional limitations.. if not, I'd suggest it's not bonding at all. But then, "Survival of the fittest" operates strongly in the corporate jungle. Well, when it comes to survival, any bond comes after 'ME', even for one's boss. Leaving apart the exceptions who go the extra mile, bonding, in my experience has failed to work in the corporate world, where it's all about cut-throat wars.
And yes, there's always a chance where bonding may somewhere also divert focus from work deliveries. Bosses can't really can't talk hard for results, deliveries on time etc. because of the personal touch (or who knows, some even do). So, bonding, in it's sanctity, is actually not done!
But, yes, as a fashionable and another wasteful word that can be used by management to adorn their hollow practices... and they call for team bonding activities, and a few also allocate budgets for team-building exercised and outing to encourage bonding among colleagues. But, that bonding as I already said is with a non-connecting emotional distance, which is like, I'm not doing this cos I wanna do it, but I'm doing this cos I have to.
I hope somebody would be able to see some reality in these words. Don't take it for a pessimistic POV, it's just experiences..