Seriously? A wheel spacer corroded and the wheel fell off? WTF??? On a C8? Can you explain this a little more please? Or, if it has been discussed elsewhere, point me there. I haven't been around here long, but as a retired mechanic something just doesn't add up. The bolt on spacers the OP linked to don't require long studs. In fact, depending on the wheel hub face pockets, the studs may have to be trimmed/ground a bit. Slip on spacers often require the OE studs to be replaced with longer ones. If you do things correctly with either type and the spacers/studs are made from a good alloy, ie not a china knock off brand, there should be no wheels falling off. Corrosion? Winter use with salty roads? How long were these on? Was torque rechecked after install and then periodically after?
Are spacers as good as different offset wheels to achieve the stance you're looking for? No. But they are an economical way to achieve a similar goal if precautions are taken with quality components, correct install procedure and torque recheck.