Not sure this is as easy as you're making it out to be.
Currently one of the biggest groups of asylum seekers, at least from the latest figures I can find, are Syrian.
Now lets supposed some has fled Syria and has all their documentation with them, they also have a working bank card with a bank that is operational and they have money in their account. If they are able to complete the online application do you think if they turn up at their screening it is going to be believed they're popping over for a holiday?
How would obtaining a tourist visa by deception impact any future asylum application?
An Act to amend and replace the present immigration laws, to make certain related changes in the citizenship law and enable help to be given to those wishing to return abroad, and for purposes connected therewith.
www.legislation.gov.uk
If it was that easy wouldn't the government be broadcasting this all over calais. You'd stop the boats in an instant if you told people they could get a visa and book a £50 EasyJet flight.