If you mean the AdSense terms and conditions, then yes if people break these they're not going to get paid. If you mean the Google webmaster guidelines, then you'll still get paid, but your site might get penalised in their SERPs.
So, hidden text for example is Ok with adsense/terms. Does it mean you can use it and still get payed ?
Webmaster Guidelines In addition to the standards above, AdSense participants are required to adhere to the webmaster guidelines posted at http://www.google.com/webmasters/guidelines.html. Some relevant items from the guidelines are included below for your reference: Do not load pages with irrelevant or excessive key words. Do not employ cloaking or sneaky redirects. Do not create multiple pages, subdomains, or domains with substantially duplicate content. Avoid hidden text or hidden links. Keep the links on a given page to a reasonable number (fewer than 100). Do not participate in link schemes designed to increase your site's ranking or PageRank. In particular, avoid links to web spammers or "bad neighborhoods" on the web as your website may be affected adversely by those links. Though it would be nice if google would provide us a list of these so-called bad neighborhoods. Otherwise how are we suppose to know.