Poor Product Reviews? No Problem. Just Erase Them!!

A few months ago a poster gave a link for an inexpensive Ultrasonic Record Cleaner. The link lead to a big box store which has store all over the US, though housed in AR. I have used this store quite often in the past due to the fact that it is close  and is very convenient. So the deal was really good and I had been wanting to try a US but could not afford.
So I ordered it and it came with the wrong US cleaner. The record rack and motor were very nice but I wanted the correct cleaner. So I start the process of exchange...or  so I thought. First, no phone # so I called the big box who gave me info. This lead to a voice mail. So I had to email. No problem at first but there was a language barrier IMO. After 2 days I finally got them to understand and they told me to send it back for a refund and reorder the product. This is unacceptable IMO.
While in the process I went to the website and looked at the  reviews. There were about 20 of them all with one star, mostly due to poor service of some kind. Woops. Should have read Before ordering. But back to erased reviews. I went to submit my review and it was not accepted. So I went to the product page again today. There are 2 reviews with 5 star rating! The previously one star reviews all gone. NO business from me anymore. But the question becomes, how prevalent is this tactic with online sales vendors among the various retailers?