They are technically "using a scale" but don't think in this way because they are following the sounds that they want to hear and 'sticking' with notes that they have figured out seem to work together to offer sounds that they like.
I think there's a precedent to how we hear notes in scales - which is a cultural artefact.... if I play a root, b3rd - if I play a major7 it's a little bit of a surprise.. in this way I like exploiting scales people often expect to hear a major 6th with a minor chord - but you can use both in the same bar... seems alien to some people, who aI think were raised on scales.
It's pattern playing if people approach scales and modes (etc) as tools rather than as 'frameworks'.
I disagree, it's pattern playing when people basically just regurgitate whats been presented to them. Understanding the properties of a tool and what it's designed to do allow you fully exploit it's capabilities, and when necessary, exceed them to create something unexpected. It's a jumping off point, a head start even.