It depends really, I do both. When it comes to shoes that they will be walking in I always buy the name brands because you want your tot to be comfortable especially when they are just getting their balance & starting to walk for longer distances.
But once in a while I'll buy a pair of walmart shoes if they're cute & throw them on for a run to the store when he will be going from the car seat to the cart back to the car seat.
When it comes to walking & running & playing in them, you want good, name brand shoes. But buying a cute cheap pair at Walmart to throw on for errands. No biggie.

I buy Walmart shoes for my 1-year-old because he only wears them for a short period of time when he's walking outside. When he gets to the point where he's spending long periods of time in his shoes then I'll definitely be investing in higher quality shoes.