The UK's Ministry of Defence (MoD) have thanked London 2012 organisers after British troops were offered tickets to prevent Olympic venues from looking empty.
An urgent investigation was launched after gaps were visible at a number of sites.
An MoD spokesman said: “Locog has kindly offered servicemen and women working on venue security to make use of unutilised seating when they are off duty.”
Football fans attending last night’s games at Wembley Stadium faced long queues after a problem with some tills.
Max Gore, 27, from Shepherd’s Bush, west London, said: “The queues were ridiculous.
“I didn’t have any cash and I couldn’t pay on card.
“I asked the person behind the bar if there were any cash machines and they said some had been taken out for the Olympics.”
A Visa spokesman said: “We understand that Wembley’s systems failed and therefore they were only accepting cash at the food and beverage kiosks.
“This cash only decision was made by Wembley management and not Visa.
“We are working with the Wembley team to help them fix this as soon as possible.”
Meanwhile, Scotland Yard launched an investigation after a set of keys for the venue went missing.
Locog stressed that the keys were internal and that the relevant locks have now been changed.
Scotland Yard is not treating the incident as criminal.
Sports fans attending venues today should enjoy less rain and more sun after yesterday’s changeable conditions, according to MeteoGroup UK, the weather division of the Press Association.
For Olympic events in the London area there is likely to be a lot of dry weather with spells of sunshine.