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No! Recall my first comment in this thread, pointing out that winglets increase efficiency on long haul routes, but can decrease efficiency on short haul.

I happen to live in an area with some very short haul flights, the planes on these routes do not have winglets.

http://airinsight.com/2012/04/10/winglets-a-triumph-of-marketing-over-reality/

“While more efficient at high altitude, for many flights on the US east coast and west coast, where heavy traffic areas exist, a flight may not get above FL270, and never reach the altitude at which the efficiency of winglets kicks in. And at those lower altitudes, cruising at more than M0.71 will result in an increase in fuel consumption because of the weight of the winglets and parasitic drag.”

In addition, winglets add weight to the wingtips of an aircraft, more than 1,000 pounds for a typical Boeing. This has an impact on the strength of the wing, effectively weakening wing torsional rigidity and introducing aeroelastic issues that must be compensated for, currently accomplished by the installation of about 100 pounds of depleted uranium in the leading edge to reduce the twist on the wing generated by the winglet installation. A basic 737 has a high gust tolerance, well in excess of regulatory standards, but one modified with winglets will lose much of that margin above regulatory requirements.

A rule of thumb for most aircraft is that its cost is about 3% of any additional weight carried in fuel each hour. For a winglet equipped aircraft, operating on short-haul routes with virtually no fuel efficiency benefit, a winglet equipped aircraft could, depending on operating procedures, have a negative, rather than positive, impact on fuel economy.

If you don’t believe the numbers, run a flight plan for a short-haul flight that doesn’t go above FL330 for a winglet and non-winglet equipped aircraft. The fuel differential will be about 0.5% better, not the 5% commonly repeated by pundits in the industry.

The position we take is not unique. Russian aerospace, for whom winglets are not a new technology or idea, have decided not to use them on the Sukhoi SuperJet or on the forthcoming MC-21.

The reality is that the payback for winglets will take about 10 times longer than marketing brochures would imply, unless all your flights are long-haul operations operating above FL390. For Air New Zealand’s 767s, winglets make perfect sense for their long-haul operations. For short-haul domestic operations, one must question the payback of winglets, which certainly isn’t going to be quick with a 0.5% fuel benefit. We wonder whether taking on 1,000 pounds of revenue belly cargo, rather than saving 0.5% of fuel with winglets, might generate a better economic result for an airline.

[There also is increased risk of runway overrun on landing with winglets:]

Winglets add lift to the wings, which results in faster speeds for the aircraft in ground effect. While jets typically increase speed by 7-8 knots in ground effect, winglets exacerbate that process, with speed increases of 10-12 knots once power is off. Without different operating procedures, it is easier to overrun a runway in a winglet equipped aircraft than one without winglets, as the speed change in ground effect can increase landing distances. And because winglets generate additional lift, the effectiveness of braking can be minimized unless pilots pull back on the yoke to firmly transfer weight from the nose wheel to the main gear and wings, which is not a part of normal operating procedures at many airlines. The potential for a runway overrun is more significant with a winglet equipped aircraft unless operational procedures are modified, as evidence by a couple of recent events.