It's just hard for me to take attendance listed in box scores seriously. For example, I'll just use the Bucks since I see them play a lot and the only NHL games where I live are games with really popular teams that always sell out on VS or NBC and select Wild games who are always near selling out.
This is a game against the Cavs. The listed attendance is 12,497 at the Bradley Center. That would mean that the Bradley Center would be 66.7% full. These aren't going to be the best pictures but they should show why you have to take listed attendance with a grain of salt.
When you consider over half the seating at the Bradley Center is in the upper bowl and it shows that there were several almost near empty sections plus the lower bowl not even being close to completely full it kind of makes attendance a joke. I know that's the number of people that actually bought tickets but it's not even close to the number of people that actually showed up.
For reference. Here's a picture of an Admirals game in the same building with a listed attendance of 12,627.