The need to make websites, mobile apps, and other online properties accessible to all is only going to increase as time moves on. Smart business owners will do well to get in front of this issue and make sure that their websites are ADA compliant now so that all their customers have the equal access to the resources they offer. Not just because they want to avoid a lawsuit or government action, but because it’s the right thing to do.
Hey Casey, this is one of the areas where things get a little weird because the W3 doesn’t actually have any say over the ADA guidelines, it is more than the ADA guidelines adopted the WCAG 2.0 guidelines as just that, a guideline to help. As far as I know, the tool you’ve linked to hasn’t been used in any judgements I’m aware of. Usually when it comes down to making a decision on if something is/isn’t compliant they have people use the actual PAWS tools and show what elements do/don’t work as intended or are otherwise inaccessible. Hope this helps!
The landscape of disabled access litigation related to online services has significantly changed and expanded over the past decade. Initially, the internet was an area of little concern as courts uniformly held that the ADA applied to "brick and mortar" facilities, not to cyberspace. This has changed and online accessibility is presently, and will continue to be, an area of significant investigation and litigation.

If your hotel used responsive web design when creating your online marketing strategies, you’re already meeting many of the ADA compliant regulations for hotel websites. You will still need to make some changes, but you definitely have a head start. Making the changes now, before your business is the target of a lawsuit or government action, makes good business sense.   
In 2001, for men of all working ages and women under 40, Current Population Survey data showed a sharp drop in the employment of disabled workers, leading at least two economists to attribute the cause to the Act.[52] By contrast, a study in 2003 found that while the Act may have led to short term reactions by employers, in the long term, there were either positive or neutral consequences for wages and employment.[53] In 2005 the rate of employment among disabled people increased to 45% of the population of disabled people.[54]