How is this spam? Are tiny transactions like these considered to be spam?
They send out thousands of 'micro' payments to randomly selected addresses. These payments are all sent from one key and this key has been tagged with their website address on Blockchain.info. So they hope that these thousands of users will look up the payment, which most will do as they don't know where it came from, and when doing so see their website address and go to their site and possibly sign up for the services/products they have on offer.
So essentially the same as a bulk spam email going out only here there is some cost involved.
The difference here is that spam email is free for the sender to send and takes up resources of the receivers email provider. With bitcoin the sender pays the TX fee so laxo (in this case) will need to pay the miners for confirming the transactions. They have paid a lot in TX fees alone which have gone to the miners