Is it necessarily lying?
If you go to a conference for a hobby that's tourism, right?
If you go to a conference for a hobby that's tourism, right?
ADDED: And people with hobbies/interests like, say, medieval history absolutely will attend a conference/event as part of a vacation even if it has zero connection to a day job.
That's exactly what I was told (as a statement, not as a question) by an official a few years ago when applying for a visa for a trip to Germany.
Whether attending a conference for a hobby counts as a vacation trip or a business trip would be a question for the destination country's consular affairs office.