I've never once heard of an issue with anyone bringing a Sparx or Prosharp on site. I've definitely witnessed it multiple times as well, as I've officiated nunerous tourneys of all age levels at the facility.
That being said, count me in as someone who purchased a Sparx solely because you seemingly never know what you are going to get from a manual sharpening at any rink, Pure, or the Hockey Monkey, from about exits 13 to 30 off rt. 495. Kind of sad that is the current state of the area nowadays.