Reduced food consumption after laying begins?

I have 4 Hens and a Roo.  Bantam breeds.  When I brought them home as chicks, I free ranged them to grass and bugs etc and offered a feeder with Chick Crumble until the entire 18 Kg bag was gone.  Then I switched to Starter Feed, same brand, and fed that until the bag was entirely done.  At this point the chicks were 4 months old.  At the tail end of that last bag I started getting 1 egg a day from my Easter Egger (maybe Olive Egger cause all her eggs are green???).  After 4 days of her laying, I ran out of Starter and bought a Layer feed, same brand again.  Filled the feeder the same amount I usually do.  Two days later I started getting an egg a day from my Buff Orpington.  So now Im getting 2 eggs a day, waiting on the other two hens to start.  (Barred Rock and SLW)  But I have noticed that since I started feeding the Layer feed the flock is not consuming much feed.  It seems they arent eating much of it at all.  I havent had to replenish the feeder in several days, which is not typically the case.

Should I be worried?  The last transition didnt seem to bother them, so Im not sure why this one would.  Does pellet/crumble consumption decrease upon maturity? I know Parrots will sometimes get fussy about a new food and can actually starve themselves to death rather than eat it, but Im not sure Chickens are that picky, ,right?

Thank you guys!

Well I expected them to eat a little less when they matured, but this did seem extreme. 

As far as the land goes, where they've been held has not changed.  I said I "free ranged" them, but in reality they are kept in a fenced in area.  But it is HUGE compared to the amount of hens I have, and lush with grass and foliage and tons of bugs, etc. so I consider it to be equal to being free ranged.  The rain we have been getting may have increased the worms, etc, I hadnt considered that.

The brand of food didnt change, but I suppose it is possible that the Layer feed fills them up better than the Starter feed.  I really wouldnt know.  But it has been since August 7th that I put about 6 Cups of feed in the feeder, and it literally looks as though it hasnt been touched! Id be pleased if they were relying on the grass and bugs etc to get food rather than the feed, I just wanted to make sure they were eating enough not to starve.

My eggs look great, have nice thick shells, bright orange yolks, etc.  But I have to say I DID expect them to be a little larger, LOL

I will keep an eye on the feed.  If they seem healthy and happy, I guess it doesnt matter in the long run.

Good to know! LOL I thought they looked a little on the tiny side, LOL 

I have been watching the feed and it seems like thier eating has picked up again.  Had to refill the feeder yesterday, and i watched them for along time and they were eating, so Im over the initial concern! LOL

I did get another surprise today.  I thought I had been getting 1 egg a day from my EE (A green egg) and then 1 egg a day from my BO (a small beige/brown egg with a pink tinge).  But today, I caught my EE sitting in the nestbox, and having never seen them lay one, I stayed and watched, and what do you know, when she walked out of the nest there was a pink/beige egg there!  SO maybe it has been my EE all along, two eggs a day and I have three hens not laying yet.  Haha