It means the miners are paid pure by transaction fees, so there will still be rewards and still be miners.
i think that there will be a few Miners (possibly no miners) cause the reward per block is small
That is pure speculation, by the time this happens the blocks will be halved and halved and the rewards from fees won't be too much of a change. The idea is that Bitcoin will be worth much more then and if it isn't difficulty should adjust to keep someone interested.
Actually, Satoshi predicted that we will reach an equilibrium stage where there will be only a few miners left.
I think that by the time it reaches that phase it will be very profitable for those who are left.
I also think that by the time we get to that phase Bitcoin will have been more widely adopted.
The ones who have the hashing power and can handle the running costs will be benefiting from the transaction fees.
Think of VISA, AMEX and MasterCard.
They are handling millions/billions of transacions per day.
If someone is one of the few handling the Bitcoin transactions then they will be making a shit load of money.