Everclear and tonic

Sat here sipping Everclear and tonic which my friend brought back from California. Quite sure that this 80% alcohol is illegal in UK.
Makes me ponder legality and contraband. It is just a stronger alcohol, why does a government believe it has the right to restrict it. Can we not just be responsible for ourselves?
This is a much larger topic than I have time for but, when I received my Everclear I noted the superior strength and so exercise caution, can’t we just give people a ‘heads up’ and then allow them to imbibe whatever they like?