It's not unusual for magicians to use decks other than a standard pack, like Bicycles. In fact, in Europe, it's Bicycles that are different and stand out - and they're a little expensive.
As a magician myself, I'll often use a standard deck, or at least a standard-looking deck. The reasons have nothing to do with it "looking suspicious" like a magic deck.
1) Standard faces are something the audience will identify with - "Oh, I have one at home that looks like that..." It puts them at ease.
2) Standard faces will not distract the audience, making them pay more attention to the cards and less attention to the trick.
3) Standard decks tend to cost a lot less. Performing is one of the fastest ways to trash a perfectly good deck of cards, because you never know where your audience's hands have been, so given the choice between them trashing a $15 limited edition from Kickstarter and a $4 from the corner drugstore, I'm going to the drugstore...
4) More gaffs and trick decks are available in standard designs than in custom designs - and the leader would be the Bicycle Rider Back in red, followed closely by the Rider Back in blue. In fact, as a magician, the moment I see a Rider Back in another magician's hands, I immediately get suspicious!
So it seems cool and fun to use custom decks, but the costs add up fast and standard decks often end up being the better alternative - and if not standard decks, at least inexpensive decks with standard faces. Some of my go-to decks are:
Bicycle "Standard"
Tally Ho
Bicycle Guardians
Bicycle Masters
Monarchs
NOCs
Bicycle Split Spades "Discover Magic" deck - a stripper deck in the same design as the blue Split Spades Lions by David Blaine.
Bicycle Mandolin Backs
Bicycle Maiden Backs
Bicycle Ghost
Bicycle White Ghost
Arcane (usually just the white deck, sometimes the black one)
Classic Twins
I used to occasionally bust out packs for specific purposes - like using Bicycle Karnival Dose Redux for performing in a nightclub because of the funky, gothy look and all that, but again, decks were getting trashed and they're expensive. I'd consider something fancy for a paid gig, perhaps, but for the most part, for everyday magic, standard or cheap custom decks are fine by me, and if I do go custom, it'll be for something that's not an expensive, rare limited edition and preferably is still in print.