Lets see:
Spend $25 that requires walking to the airport station and wait 0-15 minutes for a train, depending how you connect with it. Spend X minutes walking to your hotel assuming it's only a block or 2 away. If more than a block or 2 away, may require using TTC at a cost of $3 and then the time waiting for that service and walking to your hotel. If you have one small/medium luggage, have to haul it down the stair at Union and possible up stairs at a station that does not have an elevator or an escalator working. OK if a single person and more than 2, very expensive ride. Can run into various problems along the line.
Spend $35(?) round trip to use the bus to your hotel that requires the driver to load and off load your luggage. Depending at what hotel you are staying at, bellhop to take your luggage to/from your room. You will spend extra time on the bus making stop to drop off/pickup riders before you get to your hotel. 2 or more in your party, very expensive. Can get caught up in traffic.
Spend $50 each way for a cab and get the same service as a bus, except you only make one stop and that's your hotel. If there 2-4 in your party, very cheap. Can get caught up in traffic.
Given the fact only 17,000 airport passengers go downtown, a very expensive tourist trip for the ARL if it can get more than 50% of those passengers. The less they pickup, higher the operation cost and a very low cost recovery ratio.
One seat riders are very expensive and require higher users fees.
Your call.