Sorry but you're wrong. Ticket price if the price on the ticket and of the ticket. Same with concerts,planes, theatre, theme parks even the lottery.
Anything else is supplementary and NOT part of the price of the ticket.
I am afraid it is you that are wrong on this occasion. The ASA in particular disagrees with you, see section 3.18 of the non-broadcast CAP code which states "quoted prices must include non-optional taxes, duties, fees and charges that apply to all or most buyers". And it has been ruled on numerous occasions that prices of flights, concert/theatre tickets, etc. must include all unavoidable booking fees. Even Ryanair doesn't advertise its fares as "10p plus taxes" any more.
This is a matter of consumer protection, not of your opinion. Printing £10 on a ticket and selling it for £11.50 means the price
of the ticket, the price that you paid for it, is £11.50. The
face value of the ticket is £10. Just the same as selling a £5 coin for £44.99.
I'm not aware of the lottery having fees or surcharges by the way.