Germany's system is built on the obedience of travellers, but online services to help fare dodgers are changing attitudes

It is one of the things that never fails to amaze visitors to Germany: how come there are no barriers at tube stations? "It could never work back home," proclaim tourists from less law-abiding nations, notably Britain. "No one would bother paying."

About 3.5% of journeys on German public transport are not paid for, according to statistics from the Association of German Transport Operators (VDV). In less compliant Berlin, it is 6%. That might not sound a lot to the cynical visitor, but it's too much for the VDV, which is demanding harsher punishments for fare dodgers: an increase in on-the-spot fines from €40 to €60 (£50), and €120 for repeat offenders.

The association believes the current fine doesn't deter schwarzfahrer ("black riders") who take their chances without a ticket. The €40 fine equates to 17 journeys in Berlin, where it is sometimes possible to go for weeks, if not months, without being checked, depending on which line is used.

The VDV is also outraged at an internet "service" launched in one German city to help fare dodgers evade ticket inspectors' sporadic checks. The MVV Blitzer warns passengers in Munich where and when the usually plain-clothed inspectors are working and what they are wearing.

Oliver Wolff from the VDV is worried that not paying is becoming socially acceptable in Germany. "It's now got to the point where potential fare dodgers are organising themselves and helping each other online. It's this sort of open activity that is making travelling without a valid ticket seem less harmful," he told the Süddeutsche Zeitung.

The VDV claims fare dodging costs transport companies up to €250m a year. A further €100m is spent on ticket inspectors.

Although Germany is generally thought of as an obedient nation, exceptions do seem to apply on certain issues, especially those to do with motoring. Radio bulletins regularly include blitzermeldungen (flash warnings), which tell drivers where speed cameras appear to be working on any given day.

• This article was updated on 3 February 2012 to remove a subbing error.