I'll answer from the perspective of wrenching on bikes, which I did on a volunteer basis for a couple of years around 2006. Walmart bikes are typically made wi

I'll answer from the perspective of wrenching on bikes, which I did on a volunteer basis for a couple of years around 2006. Walmart bikes are typically made with fairly low quality components. They're a total pain to put in correct adjustment, and they rarely stay correctly adjusted for long. It's also incredibly rare that they're put together right and adjusted properly from the store. That said, I don't begrudge anybody for what they ride. If you're happy, I'm happy. If you find yourself riding more and visiting your LBS more in the future to get little annoyances taken care of, that's when it's time to spend more money on a slightly higher quality bike. And if your LBS is a bunch of dicks about your Walmart bike, by all means go find a different shop. Good shops will educate you without talking down to you and let you make the right choice for your needs. If it puts a smile on your face when you throw a leg over it, it's a good bike for you!