They could be in debt or are being paid on behalf of third parties. Cannabis doesn't attract as much attention as class A's. They could be just selling to other Lithuanians/Eastern Europeans. Other criminals wouldn't be privy to know what's going on everywhere or even in their own locality all the time.
Whilst specifically talking about the UK the scenarios are exactly the same for Ireland.
GOVERNMENT ‘SERIOUSLY UNDERSTATING’ PRESSURE MASS MIGRATION PUTS ON HOUSING
Huge demand for housing fuelled by net migration running at hundreds of thousands each year.
The government are only planning for mass migration to account for 37% of future housing demand. But that projection is based on a net migration level of 170,500 a year, lower than the levels recently seen.
A more realistic projection of net migration at 233,000 each year would mean 45% of future households were due to future net migration.
The government’s projections also ignore demand placed on housing stock by those migrants already in Britain.
Lord Green of Migration Watch has said: “We have a major crisis over housing affecting huge numbers of people but especially the young who are finding it ever harder to get onto the housing ladder.
“Yet the focus of the debate is still entirely on supply; nobody dares talk about demand and its principle driver – immigration. That has to stop.
“Our report breaks new ground in daring to point to this central, if uncomfortable truth.”
Limiting migration and bringing it down tens of thousands net per annum – as David Cameron famously promised – would stop the demand side of the housing equation from spiralling even more out of control.