Many years ago I used to buy such items at Wal Mart. Sometimes you would end up with good stuff that lasted. Once bought a clearance sport coat for $10 that I wore for a few years and got a lot of compliments on. But it was always hit and miss. A lot of times the cut wouldn't be quite right and you ended up with a lot of stuff you seldom wore because it wasn't really all that comfortable. Or the colors faded more quickly. Or the buttons or zippers failed. Over time I learned that on balance you ended up with better value at Macy's. And now that the internet allows one to shop clearance racks at better stores from the comfort of your chair, I think the value is much better from higher end stores. I learned over time that shopping wisely is ultimately more economical than shopping cheaply.

I don't think it's any different with bikes. You might get a serviceable bike from Wal Mart that suits your purpose. If you're lucky it might be a decent fit and you may not suffer from premature failure of critical parts. On the other hand, maybe not. My life experience indicates one can shop more wisely than that if they so desire. There are a lot a great older bicycles out there that are much better value.