Most people earn pretty good money in the US, but that doesn’t mean everyone gets to live like a king. Due to the high cost of living, many people find it difficult to make ends meet, and that means that luxury services like spa treatments are, well, a luxury that few can afford. But that doesn’t have to be the case. Even if you’re a low earner, it’s possible to find some great discounts on spa treatments that make it a luxury you can suddenly afford. Don’t believe us? Then check out the wellness and beauty section at Groupon to…