Can you use a freestyle snowboard mainly for freeriding even though it is meant for the terrain park?

Yes.
The only problem comes in powder. If you have a twin tip, with a centered stance, you are going to be working real hard in the powder. Keep your stance a little back, and get a directional if you are never in the park anyway.
If you are never doing freestyle, consider an all-mountain board instead of a park board.

Snowboard Freestyle by DC

NO RESERVE Salomon “Grip” Park and Freestyle Snowboard 154cm NEW $0.20

Amped: Freestyle Snowboarding (Xbox, 2001) VGC CIB $1.01

NEW 2012 Rome SDS HEADLINE Mens Snowboard 158 cm Camber All Mountain Freestyle $203.55

Amped: Freestyle Snowboarding (Xbox, 2001) $2.03

NEW Burton Freestyle Mens Strap-In Snowboard Boots Slate Gray/Vanilla US 5 $71.24

Amped: Freestyle Snowboarding (Xbox, 2001) $3.04

Amped: Freestyle Snowboarding Xbox, 2001 Free Ship USA $11.31

NEW LTD Ace 158 Snowboard // All Mountain Freestyle Park Pipe Ripper Powder $71.24

NEW Lamar Skylark 158 Snowboard // All Mountain Freestyle Park Pipe Ripper $91.60

NEW Lamar Fixx 151 Snowboard // All Mountain Freestyle Park Pipe Ripper $117.05

NEW Lamar Fixx 158 Snowboard // All Mountain Freestyle Park Pipe Ripper $122.14

NEW Sims Protocol 151 Snowboard // All Mountain Freestyle Park Pipe Ripper $117.05

NEW Sims Protocol 158 Snowboard // All Mountain Freestyle Park Pipe Ripper $117.05

NEW Lamar Creeper 158 Snowboard // All Mountain Freestyle Park Pipe Ripper $71.24

NEW Lamar Skylark 154 Snowboard // All Mountain Freestyle Park Pipe Ripper $91.60

NEW Lamar Skylark 158 Snowboard // All Mountain Freestyle Park Pipe Ripper $91.60

NEW LTD Finesse 148 Snowboard // Womens All Mountain Freestyle Park Pipe Slayer $117.05

NEW Sapient Neige 152 Snowboard // Womens All Mountain Freestyle Park Pipe $117.05

NEW Lamar Prima 148 Snowboard // Womens All Mountain Freestyle Park Pipe Killer $91.60

NEW Lamar Pixie 148 Snowboard // Womens All Mountain Freestyle Park Pipe Killer $91.60

Redfeather 761707 9in. x 30in. Trek Snowshoes This shoe is extremely afordable and offers unprecedented quality. V-tail design provides an all around lightweight snowshoe for any endeavor. Sleek innovative V-tail acts like a directional rudder in powdery conditions and steep terrain which allows the most natural stride. This results in less strain on the body and causes the least amount of fatigue. Includes the Ultra binding (with Urathane he…

Snowboard: Trucos Y T‚cnicas De Freestyle / Freestyle Tips and Techniques $35.68 …

Snowboard Freestyle $30.45 …

Mountain Boy Sledworks Mountain Boggan Toboggan Pad, 4-Foot $13.89 A perfectly sized pad for the 4 foot Mountain Boggan toboggan. Mountain Boy Sledworks sports craftsmans hand made quality the Pad for Mountain Boggan makes sure youre ultra comfy on its classic styling. Crafted in the Silverton workshop in limited quantities this 1 inch thick pad has a water resistant nylon cover that attaches with a sturdy nylon strap. Offered in reversible red or green this pad …

Mountain Boy Sledworks Bambino Grande Pull Sled (Natural) $95.18 The elegantly crafted Bambino pull sled is a childs perfect introduction to winter. The cozy pull sled is designed to excel in powder and on bumpy snow as well as hard-packed snow. With a custom-molded bottom of high-quality slippery plastic it glides along with ease while its wide stance keeps it stable. The Bambino is made to last for generations with thick birch planks hand-carved willow hand r…

Technine Men’s 153 MFM Classic Snowboard $213.99 This twin freestyle snowboard is perfect for all types of riders, perfect for groomers, park, pipe, and powder. The MFM classic is designed for all levels featuring a power tech core and radial sidecut.