UK- polls about climate change do not match comments on mainstream sites?

Just curious, whenever the BBC does a piece on the heatwave the comments section quickly fills up with posts about 1976. It also fills up with people telling us that its 'just weather' and that man made climate change is 'a con by those who make money from green policies'. Generally lots of people saying there is scientific doubt.

However the scientific consensus is pretty much unanimous and a quick google shows 70% of Brits believe the climate is changing due to human activity.

So why the disconnect between BBC etc comment sections and public polls? Are people being paid to post? And if so who is funding them?