Question about clock running after offensive penalty

[footballfan23]

I noticed that after an offensive delay of game penalty (when the game clock was running), the play clock was reset, and the game clock continued to run.  It made me think, could an offensive team ahead in the second half use this tactic to run out much of the clock.

For example, if an offensive team is up by 10 points with 13 minutes in the fourth quarter and has the ball at it's own one yard line (with the clock running), could they keep taking delay of game penalties, get a half the distance to the goal penalty, and then reset the play clock and do it again?  What keeps an offensive team from running out much of the fourth quarter that way? 

[maven]

NFL 4-7-1 Note 1:

"Note 1: More than two successive delay penalties during the same down, after a warning, is unsportsmanlike conduct (12-3-1-m)."

Your QB will get ejected, and further penalties may be imposed by the Commissioner on the player and team.

Also, with 5 minutes remaining in the game, the clock will start on the snap after a DOG.

[APG]

I'm not sure about the ejection part.

Besides being charged with an unsportsmanlike penalty after the successive DOG penalty on the same down (after a warning), I would think the NFL would allow the referee to stretch the rule and deem this scenario a palpably unfair act or something to that effect and simply start the clock on the snap.