Tourists are always are welcomed change for the countless sellers, scammers and thieves in Moscow.
There are numerous reasons:
1. Russia is a very big very wealthy country with a very low average income.
2. Moscow is a very big city with a lack of common overnight accommodations like hotels, motels, Airbnb etc.
3. The outcome: everything is incredibly expensive!
4. A lot of Russians do not speak any foreign languages, not even English. They do not need to understand the tourists, the already know exactly what they want from you.
And now the global sport event, FIFA 2018, invites lots of soccer fans and tourists to our beautiful country. Every single one of them an easy prey for ruthless professionals. The will use the masses and your insecurity in an unknown setting to get to your money.