[aranazo]

Standing up while cycling makes your calves work really hard. A hour or two on one of these would make even a regular cyclist ache for a week, so a seat is probably essential for any practical purpose. The riding experience looks novel, that is probably it's main appeal.

[razster]

Stand up on your bike then and peddle. Bam saved you $1000.

[michaelmior]

Plus whatever additional money you make peddling. (peddle: to travel about selling wares, pedal: to ride a bicycle.)