"The people" aren't given the opportunity to vote on many things, yet the people they elect do vote. The people they elect often side with their supporters (especially financial ones) on issues that are important to said supporters. A candidate can use their NRA/pro gun status as part of their platform and it will have a meaningful impact on the turnout.

Logically if the US electorate cared even half as much about [topic x] as they do about guns - candidates would care too and "democracy" would follow... no?

(I'm not bashing the US, just taking gun control as an example where a passionate popular view is reflected democratically)