It has its uses, which seem to be many and various. Although, I can't say that I use it more than a few times a year.
For instance, you can type Pyongyang to Washington, DC, and it will give you basic stats on the trip and the endpoints, together with a nice map showing the great circle route:
It also offers to enlarge or customize the map, but Tilt! That requires a Pro subscription.
You can get a nutritional analysis for, say, 1 lb of cherries, and it will display an official-looking nutrition label, together with additional data.
You can look up a chemical compound, say octanitrocubane, and it will list basic facts and show you a diagram of the molecule.
You can get the sales tax for a random zip, eg., Sales tax 80906, and it will show the total rate together with the state, county, city breakdown.
You can key in your SSN, say 042684425, and receive copious useless info about it, such as its prime factorization and the fact that it is odd. To Wolfram's credit, they do provide a link to treat it as an SSN. If you click that, you find out it is a Connecticut SSN, even though, oddly, it was issued to a Hawaii resident.
You can ask it about a date and place, say 4 August 1961 in Honolulu, and it will tell you that that was 55 years 11 months 21 days ago, that sunrise was at 6:06am and sunset at 7:09pm, that two famous people were born that day, and that the city center's elevation was 16 ft (is it still?).
It does mortgages, e.g., What is the monthly payment on a $300000 mortgage at 4%? Except, oops, it's wrong. Apparently, $-signs confuse it. If you leave out the dollar sign, What is the monthly payment on a $300000 mortgage at 4%?, it gets the right answer (the correct answer according to my HP 12C is $1432.25).
But if you really want to confuse it, ask How many Pro subscribers does Wolfram Alpha have?