The latter (bad service), most likely. If you google Gainsaver, you'll find it has a 7 or 8/10 review average on some sites, but most of the 5-star reviews made were on the same day and the same "writing style". Be cautious.
BBB lists almost 300 customer complaints made in the past 3 years, which is not a good sign for a relatively small company. I also see a multipage thread on other forums dealing with complaints on Gainsaver. Many of the complaints are GS sending a different product than advertised. Then, when asked to exchange, GS either: 1) Takes back the product but doesn't send a new one; 2) Exchanges the item, but sends another irrelevant product; or 3) Doesn't respond when contacted
Tread caution.